A Software Tool to Support Scenario-Based Formal Specification for Error Prevention

Formal specification can be an error-prone process for complex systems and how to efficiently write correct specifications is still a challenge for practitioners in industry. This paper presents a software tool to support the scenario-based formal specification approach developed in the SOFL formal engineering method. Using the tool, some suggestion of the further contents of the specification may be automatically predicated to facilitate the user in completing the specification. To improve the readability of the formal specification, the tool can also automatically translate the textual format of the specification into a comprehensible tabular format. Both of these functions can be helpful to prevent errors during the construction of the specification. We discuss each of the functions by first presenting its principle and then illustrating it with examples. We present a case study to show how the tool supports the scenario-based specification approach. Finally, we conclude the paper and suggest topics for future research

Revisión sistemática de la literatura: aplicación de seguridad a requerimientos software de sistemas críticos ferroviarios

Entre los sistemas críticos más reconocidos se encuentran los sistemas ferroviarios, ya que un fallo en los mismos puede generar daños económicos, ambientales o a la vida de las personas, por lo que su análisis y tratamiento cobra especial relevancia, sobre todo en cuanto a la seguridad. En esta revisión sistemática se hace un análisis exhaustivo de la información existente en cuanto a la gestión de requerimientos software en sistemas críticos ferroviarios con la finalidad de conocer sus principales características de implementación. La revisión sistemática se realizó sobre cuatro repositorios académicos distintos (ACM, Science Direct, Springer e IEEE), obteniéndose un total de 23 publicaciones, las cuales han sido analizadas para obtener información categorizada en 5 dimensiones distintas para ayudar a su comprensión. Como conclusión, se informan los resultados de la aplicación de dicho procedimiento, indicando los principales hallazgos obtenidos de este análisis.Sociedad Argentina de Informática e Investigación Operativ

Revisión sistemática de la literatura: aplicación de seguridad a requerimientos software de sistemas críticos ferroviarios

Entre los sistemas críticos más reconocidos se encuentran los sistemas ferroviarios, ya que un fallo en los mismos puede generar daños económicos, ambientales o a la vida de las personas, por lo que su análisis y tratamiento cobra especial relevancia, sobre todo en cuanto a la seguridad. En esta revisión sistemática se hace un análisis exhaustivo de la información existente en cuanto a la gestión de requerimientos software en sistemas críticos ferroviarios con la finalidad de conocer sus principales características de implementación. La revisión sistemática se realizó sobre cuatro repositorios académicos distintos (ACM, Science Direct, Springer e IEEE), obteniéndose un total de 23 publicaciones, las cuales han sido analizadas para obtener información categorizada en 5 dimensiones distintas para ayudar a su comprensión. Como conclusión, se informan los resultados de la aplicación de dicho procedimiento, indicando los principales hallazgos obtenidos de este análisis.Sociedad Argentina de Informática e Investigación Operativ

Revisión sistemática de la literatura: aplicación de seguridad a requerimientos software de sistemas críticos ferroviarios

Entre los sistemas críticos más reconocidos se encuentran los sistemas ferroviarios, ya que un fallo en los mismos puede generar daños económicos, ambientales o a la vida de las personas, por lo que su análisis y tratamiento cobra especial relevancia, sobre todo en cuanto a la seguridad. En esta revisión sistemática se hace un análisis exhaustivo de la información existente en cuanto a la gestión de requerimientos software en sistemas críticos ferroviarios con la finalidad de conocer sus principales características de implementación. La revisión sistemática se realizó sobre cuatro repositorios académicos distintos (ACM, Science Direct, Springer e IEEE), obteniéndose un total de 23 publicaciones, las cuales han sido analizadas para obtener información categorizada en 5 dimensiones distintas para ayudar a su comprensión. Como conclusión, se informan los resultados de la aplicación de dicho procedimiento, indicando los principales hallazgos obtenidos de este análisis.Sociedad Argentina de Informática e Investigación Operativ

Mathematics in Software Reliability and Quality Assurance

This monograph concerns the mathematical aspects of software reliability and quality assurance and consists of 11 technical papers in this emerging area. Included are the latest research results related to formal methods and design, automatic software testing, software verification and validation, coalgebra theory, automata theory, hybrid system and software reliability modeling and assessment

The totalitarian model revisited : an assessment of the post-Mao regime change

Two decades of Chinese reforms have brought about a considerable change in many aspects of post-Mao China. While many have begun to talk with great relish about the changes and even rejoice in celebrating some fundamental changes in China, those critical or fundamental aspects of the Chinese communist system and central realities of China tend to be pushed aside, neglected, and very rarely mentioned. The actual picture of the empirical world is one with two sides. A comprehensive and all-sided assessment of the twenty-year change will counterbalance the one-sided view and make an important theoretical contribution to the study of regime change in post-Mao China. The assessment requires a coherent and effective macro-model or conceptual framework for defining the political regime, examining what has been changed and what has not, and assessing the nature of change in the post-Mao regime and its significance in the future of China\u27s political development. However, a theoretical problem in defining regime identity of a political regime in conceptual and comparative terms is that there are no generally accepted theoretical criteria that could be used to demarcate the beginning and ending of a political regime and to assess the nature and characteristics of a regime change in communist and postcommunist countries. This dissertation attempts to address the significance of this problem, revisit the utility of the totalitarian model, and develop a refined macro-model that can serve as the means to solve the problem - as conceptual reference points to define regime identity, measure or assess, and interpret the regime change in theoretical and comparative terms. This study challenges the widespread view that post-Mao China has moved away from communist totalitarianism and the totalitarian model is no longer useful in the Chinese studies. This study applies the newly refined model to the study of regime change in post-Mao China to test if the refined model can serve as conceptual reference points that can be used to observe, explain, and evaluate the regime change in post-Mao China. On the other hand, the case study itself provides confirming evidence for the utility of the refined totalitarian model in defining regime identity of a political regime and assessing the nature of change in the political regime. Chapter I (Theoretical Framework) addresses the research problem under consideration, the importance of the problem, and how to solve this problem. The importance of this problem is elaborated as follows; first, we have to define exactly what constitutes the essence of the communist regimes, in order to specify the precise point from which a transition departed and the precise time at which the Soviet or Chinese regime ceased to be a totalitarian dictatorship. Second, we must have conceptual reference points against which to measure change. Without generally accepted reference points, we would find ourselves left without a common basis for discussing either what existed before or what has come into being. Third, studies of communism must rely, implicitly or explicitly, on a model that can be used to collect facts for their political relevance, to present them in a coherent manner, and to provide a conceptual framework for comparative communist studies. Finally, this effort helps us understand what the postcommunist regimes carry as legacies, what they are trying to overcome, and what they have accomplished so far. This is followed by the effort to revisit the utility of totalitarianism as a macromodel in defining regime identity of a political regime and assessing the nature of change in the political regime, and the attempt to establish that the totalitarian model has undeniable analytic utility in communist studies and should be amended rather than discarded. My major argument addressed to the utility of the totalitarian model is that naive falsification, lack of generally accepted theoretical criteria for defining regime identity, misuse of the conceptual categories in the study of regime change ( conceptual stretching ), and discretional use of key concepts and terms without their being clearly defined all lead to the premature abandonment of a potentially useful model in comparative analysis. Then, a great effort is made to refine the totalitarian model on more theoretical and comparative grounds so that it can serve as conceptual reference points against which to define regime identity, measure and explain the regime change in general, and enrich our understanding of specific cases in particular. This newly refined model has clearly defined and identified the distinguishing core features of a totalitarian regime from other operative features, and established the criteria for assessing and measuring the regime change of totalitarianism. Therefore, the refined model has several useful features that can serve as the means to solve the general problem proposed at the beginning of this study. For the purpose of both empirical elaboration of the refined model and practical need of this specific case study, the refined model is then put in more concrete terms by taking China as an actual case for further elaboration and defining the hard core and protective belt of Chinese communist totalitarianism according to the refined model. The hard core and protective belt of the refined totalitarian model can effectively serve as conceptual reference points against which we are able to (1) define what existed before post-Mao China or what is the original point fi-om which the post-Mao regime has departed or the change has occurred; (2) to identify what has changed and what has not, in degree or in kind, developmental or genetic in nature; (3) to explain what features of the totalitarian syndrome the regime can loss but still be totalitarian or what degree of ideological, political, legal, economic, and social change can occur but still leave the old regime\u27s identity essentially unaffected; and (4) to evaluate whether or not the post-Mao changes have made the defining features or the hard core of communist totalitarianism insignificant or have changed them altogether into something different. Chapter II (Method and Data) justifies the case study as a method for testing a theory by addressing the problem of external validity (generalizability) of the case study method in social sciences and by distinguishing statistical generalization in which a sample is used to enumerate sample fi^equencies and generalize to a larger population fi-om analytic generalization in which case studies attempt to generalize a particular set of observed results to some broader theory rather than to some population in survey research. This chapter further addresses our major concern about the validity of selected measures for assessing the change in post-Mao China by developing an operational measurement scheme which can serve as a regular, step-by-step procedure to direct the actual operation of measuring the regime change, in particular, the data collection of the ensuing case study in post-Mao China. Finally, this chapter also identifies the primary and secondary data sources to be used in the case study. Chapters III - VII apply the refined model to the study of regime change in post- Mao China to test the utility of the totalitarian model. Post-Mao China in the last twenty years has indeed experienced considerable quantitative changes that have had a great impact on socioeconomic life, compared with the situation under Mao\u27s regime. However, the question is not whether changes have taken place in some aspects of the totalitarian regime, but whether these changes have been significant enough to affect the fundamental character of the regime. The key point here is to distinguish the changes within the system and the change of the system itself. The former is developmental change within the regime or change at the operative level, while the latter is systemic change of the regime or change at the fundamental level. The nature of a political regime remains fundamentally unchanged, if its hard core or essential characteristics are sustained. Through a systematic survey of party documents and resolutions, leaders\u27 speeches and policy statements, official publications, published empirical data, and general academic studies on the post-Mao reform in English and Chinese, these five empirical chapters examine in depth post-Mao changes across the most critical empirical aspects of regime change (ideological, political, legal, social, and economic) and the most important dimensions of each of these aspects, assess their nature and significance in terms of regime change - developmental change within the regime or systemic change of the regime, and determine whether post-Mao China can still be described as totalitarian or if those changes have transformed the post-Mao regime into post-totalitarianism, authoritarianism, soft-authoritarianism, fragmented authoritarianism, market-oriented capitalism, or anything fundamentally different from communist totalitarianism. Chapter VIII draws some conclusions about a set of results observed in this case study which can be used to generalize to the theory of totalitarianism and provide confirming evidence for the utility of the totalitarian model. The findings of this study demonstrates that, in spite of incoherence among the components of the regime or inconsistency between the regime and related behavior, the practice of post-Mao reform remains not only rooted in but also committed to the hard core of communist totalitarianism, such as the universal truths of Marxist-Leninism, the ultimate goal or end-goal of communism, the ideological commitment to its fundamental principles and norms, the hard core of political, ideological, legal, social and economic systems of Chinese communist totalitarianism, and many typical totalitarian practices, which do not contradict the regime\u27s commitment to the intermediate goal of economic modernization, but make only adjustments to the action means of achieving them. The post-Mao regime has never abdicated its totalitarian political tradition and practice to transform human nature and thinking. It has continued to control over the media and require uniformity in the press and the public opinion. It has continued to stress the pedagogical role of the press in educating, transforming, and perfecting human nature to mold a new type of socialist citizens. The post-Mao regime has attempted to resurrect the political tradition and political theory of the mid-1950s and based the political doctrine and practice of the post- Mao regime on the Four Cardinal Principles, which are considered as defining the core elements of the post-Mao regime and the direction, scope, content and limits of its reform programs. The post-Mao regime has continued to consolidate and institutionalize the totalitarian party-state apparatus, which has come down fi-om Mao\u27s era, as an appendage of the communist party who decides what should be done and what steps or measures should be undertaken. The totalitarian party has continued to control and dominate all sectors of the state and has remained the locus or the core of leadership or political nucleus for all state institutions, public and social organizations. The post-Mao regime has continued to define and promulgate the constitutional rules and give orders or directives to the governmental organs in lawmaking and implementation. The party\u27s exercise of power is not limited by law. The party is the supreme lawmaker or lawgiver. Party decisions or policy changes need not be formally justified by reference to legal rules. There are no such institutions as independent judiciary, independent legal profession, independent private bar, and special public law jurisdictions for review of administrative action and the constitutionality of legislation. Laws are not made clear, noncontradictory, and accessible. The party can manipulate laws to further its own ends. Post-Mao legislative and legal reforms have not given the Chinese people and their representatives remarkably more say over important matters of the state. The communist constitution, laws, and legal system are as a matter of fact an instrument of the single one-party dictatorship to extend its control over society, maintain its political and economic order, and achieve its policy goals. The post-Mao regime has not made any substantial retreat from either the state or the civil society, though the party-state has relaxed its control over its citizens\u27 daily life, economic activities, and social mobility to correct the traditional dysfunctional system of controlling society. The administrative state and administrative society of Chinese communist totalitarianism have remained fundamentally unchanged, and the state power has continued to perform comprehensive or all-embracing functions of administration, such as the economic function of organizing major economic activities, the social function of administering major means of production and exchange, the ideological function of cultural education, and the political/legal function of maintaining socialist political and legal system. Under the world\u27s most austere license system, all social organizations have become party-led, state-licensed, or government-controlled, with no real meaning of self-government, independence, or autonomy (except those popular clubs and societies strictly limited within non-political areas). The muscle of the police apparatus has been greatly boosted to keep a tight leash on society, and party organizations have continued to penetrate and dominate almost every comer of society. The post-Mao regime has attempted to preserve the socialist character of the economy over the past twenty years since Deng\u27s reform. The goal of post-Mao economic reforms is to restructure state socialism and establish the Socialist Market Economy, which does not suggest any attempt by the post-Mao regime to transform the Chinese economy into a capitalist one or to abandon its ultimate goal of communism. Public ownership, the governance structure of state socialism, and the administrative command system have continued to dominate the Chinese economy, while a fledgling or distorted market has just started to emerge -within the general framework of state socialism and the political context of party-state power structure. The reforms have not changed the nature of economic system or gone so far as to reverse this system. All the fundamental or core features of communist totalitarianism have remained unchanged, only with the means of achieving ends being adjusted. In short, this study has provided confirming evidence for the analytic utility of the paradigm of totalitarianism, which, rather than outmoded, is still useful and applicable to the study of the Chinese communist regime. The post-Mao communist regime has remained totalitarian rather than turning into authoritarianism or soft authoritarianism or evolving away from the authoritarian regime of the Deng era. Both Mao\u27s regime and the post-Mao regime are communist totalitarianism at the fundamental level, though they do have many differences from each other at the operative level. The change has been in degree rather than in kind; it is the developmental change within the regime rather than the systemic change of the regime

Studies relating to ground anchorage systems

This thesis comprises 28 papers which illustrate the nature and direction of development work and associated research undertaken between 1965 and 1993 on soil and rock anchorage systems. The research was performed in order to obtain a basic understanding of the behaviour of newly developed anchorage systems in a variety of ground types and conditions, in order to improve anchorage designs, construction methods and testing procedures, and thereby encourage the safe and economic application of ground anchorages worldwide. Field development of anchorage construction methods in gravels, sand, clays, marls and chalk using cement grout injection techniques is described together with equations evolved to estimate the ultimate resistance to withdrawal for each ground type, based on systematic testing of full scale anchorages. A new design method for single and multi tied stiff retaining walls installed in any soil is detailed and validated by large scale tests and closely monitored case histories. The interactions between wall, anchorage and soil are illustrated, coupled with the refinement of overall stability analyses in cohesionless soils using wedge and log spiral based mechanisms of failure. For the rapid installation of anchorages in granular soils, vibratory driving is investigated in the laboratory and two distinct types of motion are found to exist. Theoretical equations of motion are developed to define the penetration processes and facilitate the design of vibrodrivers and vibrohammers. World practice in relation to the design, construction, testing and behaviour of rock anchorages is appraised, and field studies permit an improved understanding of uplift capacity by general shear failure, load transfer mechanisms, bond at rock/grout and grout/tendon interfaces, debonding, service performance and post-failure behaviour. Acceptance criteria related to service behaviour are created for load relaxation and creep displacement with time, which are independent of ground type and potentially of short duration. The extent and nature of steel tendon corrosion is described based on an international study of the corrosion performance of post-tensioned anchorages. Guidance is provided on class of protection, design principles and acceptable protective systems. For rock tunnelling by drill and blast methods of excavation, a fundamental understanding of rock bolt behaviour under static and dynamic loading is provided. Field, laboratory and finite element studies are combined to investigate the character of blast induced wave forms within a rock mass and the effect of these signatures on the rock bolt system. Attenuation relationships for peak particle velocity and peak dynamic bolt load are presented together with effect of bolt prestress, bolt length, and both single and two speed resin systems. Observations confirm that resin bonded rock bolts have a remarkable resilience to close proximity blasting, and the data provide a new understanding of stress transfer in tensioned bolts under static and dynamic conditions. A simple device to control rock bolt tensioning is developed and applied as a result of observed variations in prestress during production bolting. Ground anchorage technology is reviewed to highlight areas where further investigation and study would enhance understanding of anchorage behaviour and improve standards of practice.PUBLICATIONS INCLUDED IN THESIS: #2. HSU, T.C., LITTLEJOHN, G.S. & MARCHBANK, B.M. (1965) "Elongation in the Tension Test as a Measure of Ductility" Proc. Amer. Soc. Test. Mat., 65, 874-98. (Hsu wrote the paper and supervised the research of Littlejohn and Marchbank who provided the data.) #3. LITTLEJOHN, G.S. (1968) "Recent Developments in Ground Anchor Construction" Ground Engineering, 1(3), 32-36 & 46. #4. HANNA, T.H. & (1969) "Retaining Wall Tie-Backs" LITTLEJOHN, G.S. Consulting Engineer, May, 50-53, June, 49-52. (Hanna and Littlejohn contributed equally to this paper.) #6. LITTLEJOHN, G.S. #8. LITTLEJOHN, G.S., JACK, B.J. & SLIWINSKI, Z.J. (1971) "Anchored Diaphragm Walls - Some Design and Construction Considerations" Journal of the Institution of Highway Engineers, 18 (4), 15-29. (Littlejohn co-ordinated this paper and contributed half the data.) #13. LITTLEJOHN, G.S. & (1974) "A Case History Study of Multi-Tied Diaphragm MACFARLANE, I.M. Walls" Proc. Conf. on Diaphragm Walls and Anchorages, 113-121, Institution of Civil Engineers, London. (Littlejohn wrote the paper. Macfarlane provided technical data.) #14. LITTLEJOHN, G.S. & (1974) "Ground Anchors at Devonport Nuclear Complex" TRUMAN-DAVIES, C. Ground Engineering, 7 (6), 19-24. (Littlejohn wrote the paper. Truman-Davies supervised the field work.) #16. LITTLEJOHN, G.S. & (1975) "Rock Anchors - State-of-the-Art Part 1: Design" BRUCE, D.A. Ground Engineering, 8 (3), 25-32, 8 (4), 41-48. (Littlejohn wrote the paper and supervised Bruce's Ph.D. programme.) #18. LITTLEJOHN, G.S. & (1975) "Rock Anchors - State-of-the-Art Part 2; BRUCE, D.A. Construction" Ground Engineering, 8 (5), 34-45, 8 (6), 36-45. (Littlejohn wrote the paper and supervised Bruce's Ph.D. programme.) #19. LITTLEJOHN, G.S. & (1976) "Rock Anchors - State-of-the-Art Part 3: Stressing BRUCE, D.A. and Testing" Ground Engineering, 9 (2), 20-29, 9 (3), 55-60, 9 (4), 33-44. (Littlejohn wrote the paper and supervised Bruce's Ph.D. programme.) #20. LITTLEJOHN, G.S., (1977) "A Study of Rock Slope Reinforcement at Westfield NORTON, P.J. & Open Pit and the Effect of Blasting on Prestressed TURNER, M.J. Anchors" Proc. Conference on Rock Engineering, University of Newcastle-upon-Tyne, England. (Littlejohn wrote the paper. Norton and Turner provided technical data.) #22. LITTLEJOHN, G.S., (1977) "Anchor Field Tests in Carboniferous Strata" BRUCE, D.A. & Revue Francaise de Geotechnique No. 3, DEPPNER, W. January 1978, 82-86. (Littlejohn wrote the paper. Bruce and Deppner provided field data.) #28. LITTLEJOHN, G.S. & (1979) "Long Term Performance of High Capacity Rock BRUCE, D.A. Anchors at Devonport" Ground Engineering, 12 (7), 25-33. (Littlejohn and Bruce jointly wrote the paper. Bruce provided the field data under the supervision of Littlejohn.) #29. LITTLEJOHN, G.S. #30. LITTLEJOHN, G.S. #32. RODGER, A.A. & (1980) "A Study of Vibratory Driving in Granular Soils" LITTLEJOHN, G.S. Geotechnique, 30 (3), 269-93. (Rodger and Littlejohn jointly wrote the paper. Littlejohn supervised Rodger's Ph.D. programme) #34. LITTLEJOHN, G.S. (1981) "Acceptance Criteria for the Service Behaviour of Ground Anchorages" Ground Engineering, 14 (3), 26-29 & 36. #36. LITTLEJOHN, G.S. #50. LITTLEJOHN, G.S. (1987) "Ground Anchorages : Corrosion Performance" Proc. Instn. Civ. Engrs., Part 1, 82, 645-662. #51. LITTLEJOHN, G.S., (1987) "Monitoring the Influence of Blasting on the RODGER, A.A., Performance of Rock Bolts at Penmaenbach MOTHERSILLE, D.K.V. Tunnel" & HOLLAND, D.C. Proc. Int. Conf. on Foundations and Tunnels, University of London, 1,99-106. (Littlejohn and Rodger jointly wrote the paper and supervised Mothersille's and Holland's research work.) #52. LITTLEJOHN, G.S. (1988) "Sprayed Concrete for Underground Support" Proc. 3rd Int. Conf. on Underground Space and Earth Sheltered Buildings, Shanghai, China. #53. LITTLEJOHN, G.S. (1988) "Rock Anchorages for Underground Support" Proc. 3rd Int. Conf. on Underground Space and Earth Sheltered Buildings, Shanghai, China. "Thermal Behaviour of Grouted Supports for Pipelines" Department of Energy - Offshore Technology Report 'Grouts and Grouting for Construction and Repair of Offshore Structures', OTH 88289, 111-120. (Littlejohn and Hughes jointly wrote the paper. Hughes provided the laboratory data under Littlejohn's supervision.) #56. RODGER, A.A., (1989) "Instrumentation Used to Monitor the LITTLEJOHN, G.S., Influence of Blasting on the Performance of HOLLAND, D.C. & Rock Bolts at Penmaenbach Tunnel" MOTHERSILLE, D.K.V. Proc. Conf. on Instrumentation in Geotechnical Engineering, University of Nottingham, 267-279. (Rodger and Littlejohn jointly wrote the paper and supervised Mothersille's and Holland's research work.) #58. LITTLEJOHN, G.S., (1989) "Dynamic Response of Rock Bolt Systems" RODGER, A.A., Proc. Int. Conf. on Foundations and Tunnels, MOTHERSILLE, D.K.V. University of London (Sept.), 2, 57-64. & HOLLAND, D.C. (Littlejohn and Rodger wrote the paper and supervised Mothersille's and Holland's research work.) #61. LITTLEJOHN, G.S. #62. LITTLEJOHN, G.S. #64. LITTLEJOHN, G.S. #74. RODGER, A.A., (1993) "Dynamic Response of Rock Bolts at Pen y Clip LITTLEJOHN, G.S., Tunnel in North Wales" HOLLAND, D.C. & Proc. Int. Cong, on Options for Tunnelling, Int. XU, H. Tunnelling Assoc., Amsterdam. (Rodger and Littlejohn jointly wrote the paper and supervised Holland's and Xu's research.) #75. LITTLEJOHN, G.S. (1993) "A Simple Device to Control Rock Bolt Tensioning" & CONWAY, J. Tunnels & Tunnelling, (in press). (Littlejohn and Conway jointly wrote the paper. Littlejohn planned and supervised the experimental work.